It would have been interesting to see how Salo had done in the M3. I think that lap had been faster than the one he did in the merc.....

Yeah, I had the exact same thought. The testing methodology for the track time isn't particularly accurate - former F1 pro v. a talking head. The driving skill of the pro would presumably skew the results somewhat.

This is why Top Gear's "Stig" was so great - he gave the results a sense of reliability.